Good: caliber

Bad. calaber

The word can mean very competent or the degree of merit. It can also refer to the inside of the barrel of a gun. I’ll use a gun visual image to remember the spelling. It is the middle of the word I spell wrong. But think of the .i. as the barrel of a gun with a bullet exiting. Thus it is spelled with an i.

Do you have a better idea? If you do, please share in the comment section of the blog.